Electrochemical conversion of dinitrogen to ammonia induced by a metal complex–supported ionic liquid

• The electrochemical synthesis of NH3 from N2 and proton by using Cp2TiCl2.
• The yield of NH3 per Cp2TiCl2 in ionic liquid was higher than that in organic solvent.
• The ionic liquid assists in the dissociation of Cl anion from the Cp2TiCl2 and promotes a decrease in the activation energy.

Electrochemical synthesis of NH3 from dinitrogen and protons from water by using Cp2TiCl2 supported in a hydrophobic ionic liquid, 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate ([C9H20N]+[(C2F5)3PF3]−), was achieved in a solid polymer electrolyte (SPE) cell under ambient conditions. The yield of NH3 per Cp2TiCl2 and current efficiency are 27% and 0.2%, respectively, which are improved in comparison with those reported previously.